Cisco Cisco Packet Data Gateway (PDG)
System Settings
Configuring a Demux Card ▀
ASR 5500 System Administration Guide, StarOS Release 18 ▄
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Configuring a Demux Card
You can dedicate a DPC/UDPC or DPC2/UDPC2, or MIO/UMIO to function as a demux card. Demux is a generic term
for signal demultiplexing tasks. These are the tasks are responsible for parsing call setup (signaling packets) and
distributing the calls internally. For this reason there almost as many tasks running on a demux card as there are
services.
for signal demultiplexing tasks. These are the tasks are responsible for parsing call setup (signaling packets) and
distributing the calls internally. For this reason there almost as many tasks running on a demux card as there are
services.
The vpnmgr tasks responsible for each context also run on the demux card. The number of vpnmgr tasks correspond to
the number of contexts. A vpnmgr is responsible for IP address assignment to mobile equipment, IP routing (such as
BGP, OSPF), as well as a variety of associated tasks.
the number of contexts. A vpnmgr is responsible for IP address assignment to mobile equipment, IP routing (such as
BGP, OSPF), as well as a variety of associated tasks.
Overview
Designating a DPC/UDPC or DPC2/UDPC2, or MIO/UMIO as a demux card frees up resources for session handling,
which has the potential to increase system throughput. However, there is no increased support in total subscriber
capacity due to other system resource restrictions.
which has the potential to increase system throughput. However, there is no increased support in total subscriber
capacity due to other system resource restrictions.
This feature is disabled by default and can be enabled via the Global Configuration mode require demux command. It
is only supported for a limited number of products. Refer to the product Administration Guide for additional
information.
is only supported for a limited number of products. Refer to the product Administration Guide for additional
information.
To support this feature session recovery must also be enabled via the Global Configuration mode require session
recovery command.
recovery command.
Important:
After enabling demux card and session recovery, you must save the configuration and reboot the
ASR 5500 to enable this feature.
Caution:
Enabling the Demux on MIO/UMIO feature changes resource allocations within the system. This
directly impacts an upgrade or downgrade between StarOS versions in ICSR configurations. Contact Cisco TAC for
procedural assistance prior to upgrading or downgrading your ICSR deployment.
procedural assistance prior to upgrading or downgrading your ICSR deployment.
MIO Demux Restrictions
The following restrictions apply when enabling an MIO/UMIO as a demux card:
The require demux management-card command must be configured before any service or contexts have been
created on the system. The command will not execute after a mode of operation has been selected for the
chassis.
chassis.
Only the following services currently support the designation of an MIO/UMIO card for demux functions:
GGSN, SGW, PGW, HA, SAE-GW and L2TP LNS. These services are supported only when they are deployed
as consumer gateways.
as consumer gateways.
SGSN, MME, HNBGW, HeNBGW, SaMOG, PDG, PDIF, ePDG, IPSG, PDSN, HSGW, L2TP LAC, NEMO,
CSCF, FA, and WSG are not supported. Enterprise or corporate gateways (GGSN, HA, PGW, etc.) are also not
supported.
supported.
You should not enable demux functionality on MIO/UMIO for configurations that require a large number of
tunnels.